I would also suggest that you get a polarity checker as well - if you are using uk appliances in europe - some european sites tough it is getting less, could be wired with reversed polarity. for appliances bought in europe it doesn't matter as they are design do work un polarised but obviously uk 3 pin is only one way

also if you are likely to venture into switzerland or Liechtenstein then you will also need another plug adapter as some site sthere still have a three pin euro plug

though very few european sites still use euro outlets for outside mains with only very small non upgraded sites having them mainly though some municipal campsites still do

a role of gaffer tape and some polythene bags are also useful to make sure no water gets in

btw currently sat on le corniche du basque 10k from the spanish border having travelled down the west coast last week

bit mixed we had terrible weather on drive to dover but it brightened up when we got to calais with only a little drizzle, down to anger hot but thunder storm in evening on Ile de Re mix of sun and showers for three nights one showery night on Les Landes and here at St jean de Luz one day of glorious sun one of slight over cast and today a grey and damp after rain last night likely to have rain again later but forecast is mixed for next few days

so far we have missed any really heavy rain and managed to get some sun burn